If it's a sycnhro problem, you won't be able to shift to certain gears.But if you lose power on 3rd and 4th gear, it could be the engine or a sliding clutch... or possibly your driving style too.
bro kung sliding sana parang may delay kaso hindi eh. di talaga bumabatak at all. ang lakas ng batak sa 1st at 2nd gear also sa 5th gear. kaya di talaga sa clutch. gusto ko lng malaman if may nakaranas dito ng ganon issue at kung magkano ang synchronizer.
[SIZE=3]Synchronizers[/SIZE]
Manual transmissions in modern passenger cars use synchronizers to eliminate the need for double-clutching. A synchro's purpose is to allow the collar and the gear to make frictional contact before the dog teeth make contact. This lets the collar and the gear synchronize their speeds before the teeth need to engage, like this:
The cone on the blue gear fits into the cone-shaped area in the collar, and friction between the cone and the collar synchronize the collar and the gear. The outer portion of the collar then slides so that the dog teeth can engage the gear.
Every manufacturer implements transmissions and synchros in different ways, but this is the general idea.